Radar level gauges are in wide use for making non-contact measurements of the level of products such as process fluids, granular compounds and other materials. These devices utilize antennas to transmit electromagnetic waves toward the material being monitored and to receive electromagnetic echoes which are reflected at the surface of the material being monitored.
However, a problem experienced in this type of level gauges is that the signal strength from a surface echo reduces significantly as a function of measured distance. In order to increase the signal strength of the received echo signal, an amplifier is typically used.
However, a common problem in systems using such amplification is that the amplifier normally requires much power. The provision of this power is relatively difficult to achieve in practice, since energy is normally a scarce resource in the above-discussed type of gauge systems. In particular, this is a problem in systems using a two wire feeding system.
Still further, most known systems have problems related to the noise level, due to the increased noise level generated by the amplification and the amplifier.